image: add busybox to list of allowed images

This image is used by sig-imageregistry tests and is currently returned by
k8s-tests external binary. However, in k8s 1.34 the busybox image was updated
and we'll need both versions to be mirrored.

Author: bertinatto

test/extended/util/image/image.go

@@ -53,8 +53,9 @@ var (
 
 		// allowed upstream kube images - index and value must match upstream or
 		// tests will fail (vendor/k8s.io/kubernetes/test/utils/image/manifest.go)
-		"registry.k8s.io/e2e-test-images/agnhost:2.53": 1,
-		"registry.k8s.io/e2e-test-images/nginx:1.15-4": 19,
+		"registry.k8s.io/e2e-test-images/agnhost:2.53":     1,
+		"registry.k8s.io/e2e-test-images/busybox:1.36.1-1": 7,
+		"registry.k8s.io/e2e-test-images/nginx:1.15-4":     19,
 
 		// used by KubeVirt test to start fedora VMs
 		"quay.io/kubevirt/fedora-with-test-tooling-container-disk:20241024_891122a6fc": -1,